The invention relates to a stabilizing strut for a chassis of a vehicle.
A stabilizing strut is used as a structural component of a chassis of a vehicle. The stabilizing strut may be, for example, a track control arm which forms part of the wheel suspension of two-track vehicles and is articulated to the body and wheel carrier of the vehicle. A stabilizing strut within the meaning of the present invention may also be a so-called Watts strut which forms part of a Watts linkage, which is used primarily in vehicles with rigid axles in order to reduce lateral movements of the rigid axle.
However, a stabilizing strut according to the invention is not restricted to these applications.
In general, the stabilizing strut for a chassis of a vehicle on which the invention is based has an elongated strut body made of sheet metal which has at least one first eye at a first longitudinal end and at least one second eye at a second longitudinal end. The eyes serve as bearing eyes for attaching the stabilizing strut, for example, to the body at one end and to the wheel carrier at the other end. A component such as an elastic bearing may be received in at least one of the end eyes.
The stabilizing strut according to the invention has, in particular, a strut body having a curvature at least such that the strut body lies completely outside an imaginary connecting straight line between the at least one first and the at least one second eye in at least a partial region of its length. Such a curved configuration of the strut body may be determined by the installation situation of the stabilizing strut in a vehicle, for example if a further chassis component, around which the strut body must pass, is arranged on the connecting straight line between the eyes.
The requirements of high stiffness, high resistance to buckling, capacity to transmit large forces and, in addition, simple, low-cost manufacturability, are generally placed on a stabilizing strut for a chassis of a vehicle.
Stabilizing struts which are produced in one piece, that is, from a single metal sheet, are known. In this case a sheet metal blank, usually a sheet steel blank, is subjected to a plurality of forming processes in order to obtain, for example, a U-shaped profile in cross section, the peripheral edges of the sheet metal additionally being flanged or bent over in order to increase stiffness. There are also known stabilizing struts of one-piece construction in which the sheet metal is formed to such an extent that the strut body has an almost closed box-shaped profile in cross section perpendicularly to the longitudinal direction.
The disadvantage of the one-piece construction of stabilizing struts is that, because of the plurality of forming processes to which the sheet metal blank is subjected, a sheet metal blank of low sheet thickness made of a material of low strength must be used, which, however, reduces the inherent stiffness of the stabilizing strut produced in this way. In other words, only relatively soft sheet metal can be used for such a stabilizing strut, in order to make possible the complex forming processes without rupture or fracture of the material. If, in addition, the strut body has a large curvature, the aforementioned forming processes can be implemented only with a still softer starting material, still further reducing the inherent stiffness of the stabilizing strut produced in this way.
If the sheet metal is formed to such an extent that the strut body has an almost closed box-shaped profile in cross section perpendicularly to the longitudinal direction, the inherent stiffness of the stabilizing strut can thereby be increased; however, the internal surfaces of the closed box-shaped profile are no longer accessible for subsequent coating or painting.
Stabilizing struts which are likewise produced from a sheet metal which is not only formed by bending and folding processes but is deep-drawn in order to produce the strut body are also known. The manufacture of a stabilizing strut of one-piece construction by means of numerous forming processes with a high degree of forming, whether by folding, bending, deep-drawing or the like, has the disadvantage of high tooling costs, with the result that the production of the stabilizing strut is cost-intensive. In addition, the time requirement for producing the stabilizing strut is disadvantageously high, which also contributes to increased cost.
Stabilizing struts which have a two-part construction are also known. In the case of these known stabilizing struts two sheet metal parts forming the strut body are joined to one another at their peripheral edges over their entire length by means of continuous weld seams. The disadvantage of this construction is that the cost and complexity of production are increased by the joining of the peripheral edges of the sheet metal parts over their entire length. A further disadvantage is that, viewed in cross section, the strut body has a closed profile over almost its entire length, making it impossible or at least more difficult to paint or coat the internal surfaces of the strut body subsequently, in order to protect the interior of the stabilizing strut from corrosion.